The empirical formula : Na₂Cr₂O₇
Further explanation
Given
170 g sample contains :
29.84 g sodium, 67.49 g chromium, and 72.67 g oxygen
Required
The compound's empirical formula
Solution
mol ratio of elements :
Na : 29.84 : 23 g/mol = 1.297
Cr : 67.49 : 51,9961 g/mol = 1.297
O : 72.67 : 16 g/mol = 4.54
Divide by 1.297
Na : Cr : O = 1 : 1 : 3.5 = 2 : 2 : 7
